To get all of the 950's features, you'll need a 7-channel amp like the upcoming Outlaw 770. A number of folks (myself included) will be using a 750 and a two-channel amp.
The 1050/750 combo is for people who want more power than a receiver typically offers. The 1050 has become notorious for how much power it actually has with a rating of only 65W per channel (it sounds like a good deal more than that in most people's opinion), but the 750 is rated at 165W per channel -- a lot more.
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Gonk